:root {
  --bg: #f7f7f5;
  --panel: #ffffff;
  --text: #1d1d1f;
  --muted: #6b6b70;
  --border: #dcdcdf;
  --accent: #2f5fd0;
  --pass: #1f8a4c;
  --fail: #c62f2f;
  --warn: #b26a00;
  --code-bg: #f0f0ee;
  --caret: #1d4ed8;
  --syntax-comment: #7a7f87;
  --syntax-string: #a1441b;
  --syntax-number: #0b7a75;
  --syntax-keyword: #8a2be2;
  --syntax-variable: #2f5fd0;
  --syntax-field: #1d1d1f;
  --syntax-operator: #6b6b70;
  color-scheme: light;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #141416;
    --panel: #1e1e21;
    --text: #e8e8ea;
    --muted: #9a9aa2;
    --border: #34343a;
    --accent: #7aa2ff;
    --pass: #4cc38a;
    --fail: #ff6b6b;
    --warn: #f0a640;
    --code-bg: #2a2a2e;
  --caret: #ffcc4d;
    --syntax-comment: #8b919a;
    --syntax-string: #f0a07a;
    --syntax-number: #5fd3cc;
    --syntax-keyword: #c79bff;
    --syntax-variable: #7aa2ff;
    --syntax-field: #e8e8ea;
    --syntax-operator: #9a9aa2;
    color-scheme: dark;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 14px/1.45 system-ui, -apple-system, "Segoe UI", sans-serif;
}

header {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 8px 24px;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
}

h1 { margin: 0; font-size: 18px; }
h1 span { color: var(--muted); font-weight: 400; }
h2, h3 { margin: 0 0 8px; font-size: 13px; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); }
h3 { margin-top: 12px; }
#status { margin: 0 0 0 auto; color: var(--muted); font-size: 12px; }
.sample { color: var(--muted); font-size: 13px; display: flex; gap: 8px; align-items: baseline; }
.sample select { padding: 2px 4px; max-width: 70vw; }
#share { font: inherit; font-size: 13px; padding: 2px 10px; background: var(--panel); color: var(--text); border: 1px solid var(--border); border-radius: 4px; cursor: pointer; }
#share:hover { border-color: var(--accent); }
#share-status { margin: 0; }
.about { flex-basis: 100%; margin: 0; color: var(--muted); font-size: 12px; }
a { color: var(--accent); }

main {
  display: grid;
  grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
  grid-template-areas: "expr input" "output output";
  gap: 16px;
  padding: 16px;
}

#expression-panel { grid-area: expr; }
#input-panel { grid-area: input; }
#output-panel { grid-area: output; }

@media (max-width: 800px) {
  main { grid-template-columns: minmax(0, 1fr); grid-template-areas: "expr" "input" "output"; }
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px;
  min-width: 0;
}

.editor { border: 1px solid var(--border); border-radius: 6px; overflow: hidden; }
/* The editor's own colors are a CodeMirror theme (editorTheme in main.js). */
.editor:focus-within { border-color: var(--accent); box-shadow: 0 0 0 2px color-mix(in srgb, var(--accent) 30%, transparent); }
.cm-tooltip { background: var(--panel) !important; color: var(--text); border: 1px solid var(--border) !important; border-radius: 6px; max-width: 420px; }
.cm-tooltip .md { padding: 6px 10px; }
.cm-tooltip-autocomplete ul li[aria-selected] { background: var(--accent) !important; color: #fff !important; }
.md p { margin: 4px 0; }
code, .md code { font-family: ui-monospace, "Cascadia Code", Menlo, Consolas, monospace; font-size: 12px; background: var(--code-bg); border-radius: 3px; padding: 0 3px; }

textarea {
  width: 100%;
  caret-color: var(--caret);
  min-height: 260px;
  resize: vertical;
  font: 12px/1.45 ui-monospace, "Cascadia Code", Menlo, Consolas, monospace;
  background: var(--panel);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px;
}
textarea.short { min-height: 70px; }

.hint { color: var(--muted); font-size: 12px; margin: 8px 0 0; }
#signature { min-height: 1.4em; font-family: ui-monospace, Menlo, Consolas, monospace; color: var(--text); }
#signature strong { color: var(--accent); }
.error { color: var(--fail); }
#input-error:empty { display: none; }

.tabs { display: flex; flex-wrap: wrap; gap: 4px; align-items: center; border-bottom: 1px solid var(--border); margin-bottom: 12px; }
.tabs button {
  border: 0; background: none; color: var(--muted); padding: 8px 12px; cursor: pointer;
  font: inherit; border-bottom: 2px solid transparent; margin-bottom: -1px;
}
.tabs button[aria-selected="true"] { color: var(--text); border-bottom-color: var(--accent); }
.tabs .level { margin-left: auto; color: var(--muted); font-size: 12px; display: flex; gap: 6px; align-items: center; }
select { font: inherit; background: var(--panel); color: var(--text); border: 1px solid var(--border); border-radius: 4px; }

pre { margin: 0; overflow: auto; font: 12px/1.45 ui-monospace, Menlo, Consolas, monospace; white-space: pre-wrap; overflow-wrap: anywhere; }

#explanation { list-style: none; margin: 0; padding: 0; font-size: 13px; }
#explanation li { padding: 3px 0 3px calc(var(--depth, 0) * 18px); cursor: pointer; }
#explanation li:hover { background: var(--code-bg); }
#explanation .explanation-result { cursor: default; padding-bottom: 8px; }
#explanation .message { color: var(--muted); margin-left: 22px; font-size: 12px; }
.icon { display: inline-block; width: 18px; text-align: center; }
.passed-true, .outcome-true > summary .icon { color: var(--pass); }
.passed-false, .outcome-false > summary .icon { color: var(--fail); }
.outcome-error > summary .icon { color: var(--warn); }

.audit-header { color: var(--muted); font-size: 12px; margin: 0 0 8px; }
.audit-node { margin-left: 14px; }
.audit-node > summary { cursor: pointer; padding: 2px 0; display: list-item; overflow-wrap: anywhere; }
.audit-node > summary .label { margin-right: 6px; }
.audit-node > summary .source { margin-right: 6px; display: inline-block; max-width: min(70ch, 70%); overflow: hidden; text-overflow: ellipsis; white-space: nowrap; vertical-align: bottom; }
.audit-node > summary .output { color: var(--muted); font-family: ui-monospace, Menlo, Consolas, monospace; font-size: 12px; }
.audit-node dl { display: grid; grid-template-columns: max-content minmax(0, 1fr); gap: 2px 10px; margin: 4px 0 6px 22px; font-size: 12px; }
.audit-node dt { color: var(--muted); }
.audit-node dd { margin: 0; font-family: ui-monospace, Menlo, Consolas, monospace; overflow-wrap: anywhere; }